Thread: ABS kicking in when it shouldn't be...

Having issues with the ABS on my wife's '04 GP, that are driving me crazy! The ABS is kicking in at low speeds when coming to a stop at a light or pulling into a parking space. This is intermittent. Some days the ABS warning light on the dash will come on, along with warnings on the center counsel display, informing that the ABS and traction control need serviced. But most of the time, none of that is displayed and the ABS will still kick in a couple times during a drive to work. It applies for just a short period of time, but enough that it scares you for a second. This occurs in moisture free driving on clean roads...

I have repaced the front hub assemblies (since the wheel bearings were shot anyways), and also replaced the passenger side ABS harness that plugs into the hub assembly, but the problem still remains.

Any ideas?

Scan data will be the only true way to see which wheel is giving an erroneous signal. Abs kicks in when it sees multiple or missing mph between each wheel. There will always 1 to 2 mph difference when turning. If the lights turning on its storing a code. If the lights not on check history.

So if the light isn't on, a scan can still bring up previous codes? The light rarely comes on, and when it does it doesn't stay on very long at all. That is why I have had a hard time diagnosing this...

Originally Posted by mikeplan14

So if the light isn't on, a scan can still bring up previous codes? The light rarely comes on, and when it does it doesn't stay on very long at all. That is why I have had a hard time diagnosing this...

Its worth a shot. I don't know how long exactly codes are stored in history but its certainly worth shot as I know they do get stored if the light comes on.

cool - that will be my next step!

I have had the same problem twice, i had the wires to the speed sensor made longer by moving the wires closer to each wheel. Solved the problem. Mechanics told me to replace speed sensor, which was not the solution.

My mom had this problem in her car, it was a faulty abs sensor if I recall correctly.

So you guys swapped in new hub assemblies (to get the new speed sensor)? I have already replaced the front hub assemblies, and returned them after a year and did it a second time (because I thought that they maybe had bad speed sensors). I have not done anything with the rear hubs, so that could be the issue maybe

I found this, seems like a reliable site: Real-Life Diagnostics - Diagnosing ABS make sure to go to the next page too..

I swapped out the front hub assemblies because the wheel bearings were shot, and then the ABS issue occurred. So I pulled the hubs back out and swapped them with the lifetime warranty. I will have to check it with the volt meter method and see if I can find anything.

Mine pulses just like that! The right rear brake was having some issues recently - the outside pad was really worn down and oddly worn (very drastically compared to the all the other pads), but the rotor was not discolored or anything. I put new pads (under lifetime warranty) and rotors on (since the rotors were well warped). The caliper seemed to float fine.... The ABS issue still plagues me.

Does anyone know what the test is with the volt meter?

I have not yet replaced the rear hub assemblies/speed sensors. I just want to make sure that one of those assemblies is the problem before I replace it.

i seem to have same problem. at low speeds my abs kicks in and my abs kicks in when i am stopping. causing me to not stop in time like i would like. i took my car in for inspection and the mechanic told me my drivers side wheel bearing is bad. so i replaced it today hoping it would cure my problem with abs and hollowing as i drive since its loud. well too bad he was wrong, noise and problem still there. has to be the passenger side.
i figured since my rotors were warped i would replace them and brakes too while i replaced my wheel bearing hub. and yet i still need another wheel bearing.
stupid cars cost a lot of money.

fixed my problem today. it was my wheel bearing.